Java 将特定的 csv 值存储到列表中

Question

CSV 看起来像这样：

    Name;Amount;Date
    Netflix;5;1.1.2021

我想为每笔费用制作不同的清单，一份用于娱乐，一份用于交通等。但是，我只想将金额存储在清单上，我该怎么做？

public class CsvReader {
    public static void readDataLineByLine(String file) {
        try {
            // Create an object of file reader class with CSV file as a parameter.
            FileReader filereader = new FileReader(file);

            // create csvParser object with
            // custom separator semi-colon
            CSVParser parser = new CSVParserBuilder().withSeparator(';').build();

            // create csvReader object with parameter
            // filereader and parser
            CSVReader csvReader = new CSVReaderBuilder(filereader).withCSVParser(parser).build();

            // Read all data at once
            List<String[]> allData = csvReader.readAll();
            List<String> entertainment = new ArrayList<>();

            // Print Data.
            for (String[] row : allData) {
                for (String cell : row) {
                    System.out.print(cell + "\t");
                    if (cell.startsWith("Netflix")){
                        entertainment.add(cell);
                    }
                }
                System.out.println();
                System.out.println(entertainment);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    public static void main(String[] args) {
        CsvReader.readDataLineByLine("tt.csv");
    }
}

Answer 1

如果你用的是opencsv，那么写下面的代码怎么样？请审核。

public class CsvReader {
    public static void readDataLineByLine(String file) {
        try {
            // Create an object of file reader class with CSV file as a parameter.
            FileReader filereader = new FileReader(file);

            // create csvParser object with
            // custom separator semi-colon
            CSVParser parser = new CSVParserBuilder().withSeparator(';').build();

            // create csvReader object with parameter
            // filereader and parser
            CSVReader csvReader = new CSVReaderBuilder(filereader).withCSVParser(parser).build();

            List<String> entertainment = new ArrayList<>();
            // changed part 
            int index = 0;
            while ((nextLine = reader.readNext()) != null) {   // 2
                // csv header exclusion condition
                if(index == 0) {
                   continue;
                }
                String name = nextLine[0];
                String amount = nextLine[1];
                if (name.startsWith("Netflix")){
                    entertainment.add(amount);
                }
                index++;
            }
            // Print Data.
            System.out.println();
            System.out.println(entertainment);
            
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    public static void main(String[] args) {
        CsvReader.readDataLineByLine("tt.csv");
    }
}

Java 将特定的 csv 值存储到列表中

Java store specific csv value to list

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opencsv